1. Field
The invention is related to encoding data signals and, more particularly, to encoding data signals for storage.
2. Background Information
As is well-known, it is common, in connection with the operation of a personal computer (PC) or other computer, to store data signals in a secondary memory or storage medium, such as a hard drive, disk or disk array, for example. Redundant disk arrays may be used to build highly available and reliable disk subsystems. Typically, the data signals are "exclusive-ORed" from some number of disks and maintained on a redundant disk and, in the event of a disk failure, the data signals on the failed disk are reconstructed using the data on surviving disks and writing this into a spare disk. However, data signals may also be lost if a second disk fails before the reconstruction is complete. Unfortunately, traditional disk arrays typically are inadequate for protecting from the loss of more than one disk. Therefore, a technique that will not lose data signals even when multiple disks fail and that, likewise, exhibits efficient performance is desirable.